There are situations where equipment assembled from a number of parts in a particular configuration must be disassembled for storage or transport or readjusted for the benefit of different users or as the result of use. For equipment used for transportation such as bicycles and wheelchairs, in addition to concern for the comfort and convenience of the user, there is additional concern for the user's safety. Thus, there is incentive to have assembly be directed towards the correct orientation and to alert the user if the situation is otherwise.
It is known in the prior art to adjust the position of a bicycle rider relative to the bicycle by adjustment of the height of the seat and the height of the handlebars above the bicycle frame. The seat is attached to a seat post that fits into a first vertical bicycle frame tube. Rotation of a seat bolt attached to the frame tightens around the seat post and holds the seat in a desired orientation relative to the front of the bicycle and at a desired height above the frame. The handlebar is attached to a bifurcated handlebar post that fits into a second vertical bicycle frame tube. A handlebar bolt passing through the center of the handlebar engages the bifurcated handlebar post. As the handlebar bolt is rotated, the sections of the bifurcated seat post separate and engage the inner surface of the second vertical bicycle frame tube, holding the handlebar at the desire height and in the desired orientation.
Readjustment, made necessary either deliberately or through use may be problematic. When another user wishes to use the bicycle, the heights of the seat and handlebar above the frame must often be adjusted. Height adjustment must be done in such a way as not to affect the orientation of the seat and of the handlebar. However, height cannot be adjusted without affecting orientation. Consequently, a bicycle user must employ an iterative process to first adjust the height, then the orientation, then the height again, etc.
Continued safe operation is of essential concern in a transporter that, unlike a bicycle, lacks fore/aft stability. However, firm attachment of a seat or handlebar to a frame by a single frangible coupling component, as by means of a pin, is undesirable since the coupling component is prone to damage, thereby also endangering components of the transporter.